Pulverizer.



W. K. LIGGETT.

PULVERIZER.

APPLICATION FILED 1113.12, 1907.

w1 hinaus J5 LM /K afl'mev UNITED f sTATEs PATENT oEEICE.

WILLIAM E. LIGGETT, or .eoLiUMEUSl omo, ASSIGNoE, BY MEsNE ASSIGNMENTS, To

`THE JEFFREY MANUFACTURING COMPANY, A CORPORATION or oHIo.

To all whom it may concern Be it known that I, WILLIAM K. LIGGETT, a citizen of the United States, residing at Columbus, in the county of Franklin and State of Ohio have invented certainy newv and useful Improvements in Pulverizers, of which the following isl a specification, reference being had therein to the accompanying drawing. i

My invention relates to 'machines for crushing and pulverizing rock of the type in which a series ofhammers are caused to rapidly rotate within a casing, the walls of which serve as the breaking surface or surfaces against which the pieces of rock are thrown by the action of the hammers; and the invention has for its object to produce a machine with an improved breaking surface in order that the crushing and pulverizing of the rock may be expeditiously accomplished,A and having other improved features of construction which will be hereinafter pointed out.

In the accompanying drawings, wherein an embodiment of my invention is illustrated-Figure 1 is a central longitudinal section of a rock Crusher and pulverizer containing my improvements. Fig. 2 is a vertical section taken on the line 2--2 of Fig. 1.

In the drawings, 1 designates the base on which is mounted and to which is suitably secured, as by the bolts 2, the casing forming the pulverizing chambler of the machine. The feed opening 3 leading into the pulverizing chamber of the casing 4is preferably situated at the top of the latter. Within the casing are mounted the rotating hammers, which may be of usual or preferred construction. As shown in the drawings, 4: represents a shaft mounted in suitable bearings and provided with a series of spiders 5, each preferably comprising four arms. The outer ends of the several spiders are connected by bars 6, on which are mounted the swinging hammers 7. The interior walls of the casing constitute the breaking surfaces against which the pieces of rock are thrown bythe rapidly revolving hammers 7 andfrom which they rebound to be again struck and hurled against the casing wall at a point in advance of that where the first contact took place,

Specication of Letters Patent. v

PULvEEIzEE. I

Patented Jan. 19, 1915.

Application led February 12, 1967. Serial No. 357,072.

and so on, the repeated action upon the pieces ofrock resulting in their rapid disintegration. In order to facilitate this action on the rock and to improve the working of the machine, I construct the inner walls or breakingsurfaces of the casing in a peculiar manner, the surfaces being so disposed thatrthe rock pieces after being thrown against the walls are -caused to rebound in such way as to be advantageously struck by the rapidly moving hammers. In the construction shown in the drawings the breaking surfaces "of the casing may be divided into three parts, a primary breaking plate or head 10, a second portion 11, the surface of which is broken to constitute a series of inclined impact surfaces, and a" third portion, designated in a general way4 by 12, having a series of separate inclined breaking surfaces, the inclination of theV latter being different from that of the impact breaking surfaces of the portionll. The breaking head 10 preferably consists of a curved plate suitably secured to the upper frame portion 15 of the machine, which serves as a backing therefor. It

extends from the feed opening 3 in a downward direction to the portion of the casing wall indicated generally at 11. The inner surface of this plate is not concentric with the axis of revolution of the hammers, but

inclines backward relative thereto, that is to say its forward edge is nearer to the path of revolution of the outer ends of the hammers than are successive rear portions of the plate. The result of this inclination of the plate to the path ofthe hammers, 1n

connection with the fact that it extends in a downward direction from thefeed opening, causes the piece of rock which is violently thrown against the plate by the action of the hammer to rebound or be deflected in -a downward and inward direction; in other words to be deflected in such direction as to bring it directly into the path of the following hammer, to be by it struck and hurled forward against a vportion of the casing wall in advance of that where the first contact took place. The second cont-act will be against one of the inclined faces 16 of the part 11 of thecasing wall. These faces 16, as indicated in Fig.

l, incline backward, relative to the paths of the hammers, to a great-er degree than does the wall of the breaking surface 10, with the result that the tendency of the rock pieces is to rebound in a direction more nearly vcoinciding with the radius of the circles described by the hammers cuttin the point of impact. The inclination o the surfaces 16 issuch that the general direction of the pieces, particularly those of larger size, as theyrebound, is inclined to and in advance of thie said 'radial line, though it must be understood that no two pieces will take exactly the same path, and this 1 have sought to indicate in the drawings. 'lhe pieces lthat rebound from the surface 11 are caught and struck by the following hammers and hurled forward, the third impact usually being against one of the surfaces, 17, of the portion 12 of the casingm--lhese surfaces 17 are inclined backward toa' greater extent than are the surfaces 16 of the portion 11, with the result that the deflection or rebound of the rock pieces nearly .corresponds with a radial line from the'fcenterofthe shaft 4 to the point of impact, or is even in a direction backward therefrom, this being indicated by the drawings. From this general statement taken in connection with the illustration of the operation of the apparatus in Fig. 1 of the drawings, several facts are to be noted. First, that the average size of the rock particles is smaller and smaller as the material advances from the hopper, or the position where the .i'irst contacts with tlre hammer arms take place, to the place of final discharge; and second, that the direction of each successive deflection or rebound of a rock particle tends to be different from that of the former rebound and to be in a direction successively more and more against or in opposition to the direction of movement of the hammers. There are marked advantages of operation incident to this. First, it is to be noted that in the upper part of the casing or where the breaking operations begin and where the rock pieces ,are relatively large, the successive blows fof the hammers do not and can not advantageously follow each other in so quick succession as when the pieces are of smaller size, and the rebound of the rockv pieces from the. first' contact-as at 10-being in a. somewhat forward direction, allow the hammers to recover from the effect ofthe rst blow before a second is delivered.- As the particles become smaller the effect of the contacts of the swinging hammers therewith is less severe, and the successive blows may advantageously follow each other in quicker succession, and this is accomplished by causing the successive rebounds of the rock particles to be more and more backward or against the direction of the rotation of the hammers.

rlhe casing is so constructed that a portion thereof constitutes a screen through which the particles of rock after being properly reduced in size are allowed to escape, and thus pass out of the machine. rlfhe screen constitutes the lower part of the casing, and in the construction illustrated comprises Vthat part of the impact casing wall designated as a whole by 12.

rlhe section 11 of the casing wall, carrying the impact surfaces 16, is preferably formed of one or more lates 18, removably secured t oabac king plece 19 by bolts 20. The plate or plates 18 are curved transversely to conform approximately to the contour of the casing, the inner or exposed surface being broken to constitute the impact surfaces 16 already described. The backing piece 19 is preferably flanged at top. and bottom, asy indicated at 21, 21. These anges rest between flanges 22, 22, formed respectively on the base and` top fra-me pieces, l and 15,'. which constitute guides or ways between which the backing piece is adjustable. Bolts and, nuts 23 are employed to hold the backing piece in position, the bolts passing through slots 24: formed in the fianges 21. 1n order to adjust the surface portion 11 of the casing toward and from the hammers, which becomes necessary accordingly as the latter are more or less worn, I employ 'an adjusting screw 25, the head of which has connection with the backing plate 19 and the screw-threaded stem of which engages with a stationary nut 26. A hand wheel 27 is provided for turning the adjusting screw, and a locking nut 28 may be employed for holding the parts rigidly after proper adjustment.

29 indicate curved bars, arranged in pairs at the opposite ends of the casing and adapted to constitute the supports for a series of bars 30 removably seated therein. These bars constitute the impact or breaking surface 12 of the casing as well as the bars of the grate or screen. They are preferably oblong in cross-section and are so disposed as to present their broad surfaces inward to constitute the inclined contact or breaking surfaces 17. Between the contiguous bars 30 are formed open spaces 31, through which the rock particles sufficiently reduced in size may pass, the surfaces 17 not only servin as impact or contact surfaces against whlch 'the rock ris broken but as guiding surfaces to direct the small pieces of broken rock to the exit openings. When the inner exposed edges of the bars have become worn, 'the bars may bev removed andl reversed, presenting a new operative surface, or entirely new bars may be substituted. For convenience of construction and assemblage, the curved supporting bars 29 in which the grate bars are mounted may be made in sections, as indicated in Fig. 1.

n order to permit the opening of the bottom of the casing so that pieces of iron or other objects that cannot be reduced sufliciently to pass through the .grate or screen may be removed, one pair of the bars 29, preferably the pair most advanced and indicated at 29 is pivotally mounted and provided with mechanism by which it maybe opened or closed as desired.

32 indicates a bar upon which the sections 29 are hung. The position of this movable portion of the grate or screen is controlled through the following mechanism: 33 is a shaft suitably mounted in the base of the machine, and from which extend crank arms 34 that are connected by links 35 with the curved supporting bars 29. The disposition of these parts is such that -they are arranged in line with each other, that is the centers of the shaft 34 and the two pivots of the link 35 are in line with eachother, when the swinging grate section is closed into place. The link and arm thus constitute a rigid lock for holding this movable grate section in working position.

36 is a lever secured to the shaft 33 and by which the latter is rocked for effecting the movements of the swinging section of the grate. It preferably carries a weight 37 that serves to assist in holding the parts in their two eXtreme positions, that is either closed or open.

38 is a curved shield adapted to close the upper rear portion of the casing. It mayV be moved to permit access to the pulverizing chamber.

I prefer to locate the opening into the pulverizing chamber at the top of the casing, as I am then enabled to utilize practically three full quadrants of the casing, as the impact or breaking surfaces, that is the upper forward and the two lower quadrants.

By disposing the braking plates 10 as shown, there is little danger of the pieces of rock flying out of the machine through the feed opening 2, as the inclinationof the plate and the force of gravity both tend to cause the rock particles after the impact to rebound in a downward or inward direction.

What I claim is: l

1. In a pulverizing machine, the combination of a set of revolving hammers, and a casing in which the hammers move, the casing having a feed opening through which material can be delivered to the hammers at the upper part of their swing, the said casing also hav' an impact surface 10 near the feed opening which is inclined inward'in the direction of rotation of the hammers, an im act surface 16, beyond the surface `10, Awhic is inclined inward at an angle greater than that of the surfacey 10, and an impact surface 17, beyond the surface 16, which is inclined inward at an angle greater than that of the surface 16, the said impact surfaces beings'o arranged that material can be driven against them successively by the hammers.

2. In a pulverizing machine, the combination of a set of revolving hammers and a casing in which the hammers move, having its inner walls arranged to constitute breaking surfaces and comprising a substantially smooth imperforate portion arranged adjacent to the feed opening and eX- tending downward and inclining inward relative to the circles of revolution of the hammers, a second imperforate portion having a broken surface to constitute faces 16 against which the rock is broken, the faces 16 inclining inward and forward relative to the circles of rotation of the hammers to a greater' degree than does the surface 10, and a third portion constituting a grate `or screen and having separated breakingsurfaces 17 inclined inward and forward to a greater degree than the surfaces 16.

3. In a rock pulverizing machine, the combination of a series of revolving hammers, a casing in which they move, having a feed opening and comprising a breaking plate adjacent the feed opening, a separable plate 18 curved so as to be approximately concentric with the paths of the revolving hammers, and a 'screen formed of bars against which the rock 'pieces are broken in the lower portion'of the casing, and means for supporting the plate 18 and for adjusting it in parallelism to itself toward and from the pathsr of the hammers along a line passing centrally through the said plate but attached to said carrier and adapted to form a part of the breaking surface of the machine.

5.. In a pulverizing machine, the combination of a rotary hammer mechanism, a casing in which the hammer mechanism revolves, the said casing being provided with a feed opening, with a pulverizing surface meters? and withl a, grate of which one section is moving the links to move the grate section i@ pivoted to swing outward, two toggleiinks, out of or into operative position. o pivoted together at their adjacent endsz, tbe in testimonywvhereoi i atiix my signaother end of one link being pivoted to the turev` in presence of t\\l'o--\:\'itnesses.

pivoted grate section and the other end of v l e w the other link being pivoted to the casing, the WILLIAM hiv LMI (I LT1' arrangement being such that the links when Witnesses:

in substantial alinernent lock the gratesec- CHARLES W. MILLER,

tion in operative position, and means for H.B. ALEXANDER. 

